Air quality near a major Middlesbrough road has been revealed as the second worse in the country.

Only Greater London has higher annual concentrations of poisonous nitrogen dioxide, according to new government data.

Levels in Middlesbrough of the potentially deadly chemical were estimated at one and half times the legal EU limit - ahead of major cities such as Birmingham, Manchester, Newcastle and Leeds.

Middlesbrough Council said breaches, at two stretches of the A66, are “not typical” of air quality across the town.

But the Department for Environment, Food and Rural Affairs (Defra) has now stepped in.

Officers will be forced to declare an Air Quality Management Area (AQMA) to target the sections between the A19 and Newport Bridge, and Hartington Interchange and Cineworld roundabout.

A separate action plan must be drawn up by next March to meet legal levels within the “shortest possible time”.

Jo Fitzgerald, from Stockton Green Party, said she was “shocked and disappointed” by the statistics.

She said: “The council were required to draw up an Air Quality Action Plan in 2015 and this plan has evidently failed to impact on the areas now required to be under Defra’s direction.

“Middlesbrough Council have applied stern restrictions since the Air Quality Management Act of 1995 and have successfully reduced the airborne chemical pollutants from industrial output in the area.

“We now need educate drivers in a new style of urban driving techniques whilst we wait for them to provide practical solutions to the congestion problems by improving the traffic infrastructure.

“Out-of-town car parks, shuttle buses for commuters and improved rail services from suburban stations would all go some way to reducing traffic on our roads.”

The areas concerned (Image: Defra)

A spokesman for Middlesbrough Council said the air quality breaches are on two “very short stretches” of the A66.

He said: “Whilst the levels in these locations are estimated, using EU modelling, to have the second highest levels of NO2 after London, these levels are not typical of the air quality for the whole town. There are no other exceedances in the town.

“There are other local authorities who are in a similar position with exceedances in small areas and there will be other local authorities with much larger affected areas.”